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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network113.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
113.0.0.0
Broadcast address
113.255.255.255
First usable
113.0.0.1
Last usable
113.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 71000000 · Integer 1895825408 to 1912602623
Reverse DNS zone
113.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110001..00000000.00000000.00000000113.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110001..00000000.00000000.00000000113.0.0.0
Broadcast01110001..11111111.11111111.11111111113.255.255.255
Split into smaller subnets/18
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

113.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1113.0.0.0/18113.0.0.1 to 113.0.63.254113.0.63.25516,382
2113.0.64.0/18113.0.64.1 to 113.0.127.254113.0.127.25516,382
3113.0.128.0/18113.0.128.1 to 113.0.191.254113.0.191.25516,382
4113.0.192.0/18113.0.192.1 to 113.0.255.254113.0.255.25516,382
5113.1.0.0/18113.1.0.1 to 113.1.63.254113.1.63.25516,382
6113.1.64.0/18113.1.64.1 to 113.1.127.254113.1.127.25516,382
7113.1.128.0/18113.1.128.1 to 113.1.191.254113.1.191.25516,382
8113.1.192.0/18113.1.192.1 to 113.1.255.254113.1.255.25516,382
9113.2.0.0/18113.2.0.1 to 113.2.63.254113.2.63.25516,382
10113.2.64.0/18113.2.64.1 to 113.2.127.254113.2.127.25516,382
11113.2.128.0/18113.2.128.1 to 113.2.191.254113.2.191.25516,382
12113.2.192.0/18113.2.192.1 to 113.2.255.254113.2.255.25516,382
13113.3.0.0/18113.3.0.1 to 113.3.63.254113.3.63.25516,382
14113.3.64.0/18113.3.64.1 to 113.3.127.254113.3.127.25516,382
15113.3.128.0/18113.3.128.1 to 113.3.191.254113.3.191.25516,382
16113.3.192.0/18113.3.192.1 to 113.3.255.254113.3.255.25516,382
17113.4.0.0/18113.4.0.1 to 113.4.63.254113.4.63.25516,382
18113.4.64.0/18113.4.64.1 to 113.4.127.254113.4.127.25516,382
19113.4.128.0/18113.4.128.1 to 113.4.191.254113.4.191.25516,382
20113.4.192.0/18113.4.192.1 to 113.4.255.254113.4.255.25516,382
21113.5.0.0/18113.5.0.1 to 113.5.63.254113.5.63.25516,382
22113.5.64.0/18113.5.64.1 to 113.5.127.254113.5.127.25516,382
23113.5.128.0/18113.5.128.1 to 113.5.191.254113.5.191.25516,382
24113.5.192.0/18113.5.192.1 to 113.5.255.254113.5.255.25516,382
25113.6.0.0/18113.6.0.1 to 113.6.63.254113.6.63.25516,382
26113.6.64.0/18113.6.64.1 to 113.6.127.254113.6.127.25516,382
27113.6.128.0/18113.6.128.1 to 113.6.191.254113.6.191.25516,382
28113.6.192.0/18113.6.192.1 to 113.6.255.254113.6.255.25516,382
29113.7.0.0/18113.7.0.1 to 113.7.63.254113.7.63.25516,382
30113.7.64.0/18113.7.64.1 to 113.7.127.254113.7.127.25516,382
31113.7.128.0/18113.7.128.1 to 113.7.191.254113.7.191.25516,382
32113.7.192.0/18113.7.192.1 to 113.7.255.254113.7.255.25516,382
33113.8.0.0/18113.8.0.1 to 113.8.63.254113.8.63.25516,382
34113.8.64.0/18113.8.64.1 to 113.8.127.254113.8.127.25516,382
35113.8.128.0/18113.8.128.1 to 113.8.191.254113.8.191.25516,382
36113.8.192.0/18113.8.192.1 to 113.8.255.254113.8.255.25516,382
37113.9.0.0/18113.9.0.1 to 113.9.63.254113.9.63.25516,382
38113.9.64.0/18113.9.64.1 to 113.9.127.254113.9.127.25516,382
39113.9.128.0/18113.9.128.1 to 113.9.191.254113.9.191.25516,382
40113.9.192.0/18113.9.192.1 to 113.9.255.254113.9.255.25516,382
41113.10.0.0/18113.10.0.1 to 113.10.63.254113.10.63.25516,382
42113.10.64.0/18113.10.64.1 to 113.10.127.254113.10.127.25516,382
43113.10.128.0/18113.10.128.1 to 113.10.191.254113.10.191.25516,382
44113.10.192.0/18113.10.192.1 to 113.10.255.254113.10.255.25516,382
45113.11.0.0/18113.11.0.1 to 113.11.63.254113.11.63.25516,382
46113.11.64.0/18113.11.64.1 to 113.11.127.254113.11.127.25516,382
47113.11.128.0/18113.11.128.1 to 113.11.191.254113.11.191.25516,382
48113.11.192.0/18113.11.192.1 to 113.11.255.254113.11.255.25516,382
49113.12.0.0/18113.12.0.1 to 113.12.63.254113.12.63.25516,382
50113.12.64.0/18113.12.64.1 to 113.12.127.254113.12.127.25516,382
51113.12.128.0/18113.12.128.1 to 113.12.191.254113.12.191.25516,382
52113.12.192.0/18113.12.192.1 to 113.12.255.254113.12.255.25516,382
53113.13.0.0/18113.13.0.1 to 113.13.63.254113.13.63.25516,382
54113.13.64.0/18113.13.64.1 to 113.13.127.254113.13.127.25516,382
55113.13.128.0/18113.13.128.1 to 113.13.191.254113.13.191.25516,382
56113.13.192.0/18113.13.192.1 to 113.13.255.254113.13.255.25516,382
57113.14.0.0/18113.14.0.1 to 113.14.63.254113.14.63.25516,382
58113.14.64.0/18113.14.64.1 to 113.14.127.254113.14.127.25516,382
59113.14.128.0/18113.14.128.1 to 113.14.191.254113.14.191.25516,382
60113.14.192.0/18113.14.192.1 to 113.14.255.254113.14.255.25516,382
61113.15.0.0/18113.15.0.1 to 113.15.63.254113.15.63.25516,382
62113.15.64.0/18113.15.64.1 to 113.15.127.254113.15.127.25516,382
63113.15.128.0/18113.15.128.1 to 113.15.191.254113.15.191.25516,382
64113.15.192.0/18113.15.192.1 to 113.15.255.254113.15.255.25516,382
65113.16.0.0/18113.16.0.1 to 113.16.63.254113.16.63.25516,382
66113.16.64.0/18113.16.64.1 to 113.16.127.254113.16.127.25516,382
67113.16.128.0/18113.16.128.1 to 113.16.191.254113.16.191.25516,382
68113.16.192.0/18113.16.192.1 to 113.16.255.254113.16.255.25516,382
69113.17.0.0/18113.17.0.1 to 113.17.63.254113.17.63.25516,382
70113.17.64.0/18113.17.64.1 to 113.17.127.254113.17.127.25516,382
71113.17.128.0/18113.17.128.1 to 113.17.191.254113.17.191.25516,382
72113.17.192.0/18113.17.192.1 to 113.17.255.254113.17.255.25516,382
73113.18.0.0/18113.18.0.1 to 113.18.63.254113.18.63.25516,382
74113.18.64.0/18113.18.64.1 to 113.18.127.254113.18.127.25516,382
75113.18.128.0/18113.18.128.1 to 113.18.191.254113.18.191.25516,382
76113.18.192.0/18113.18.192.1 to 113.18.255.254113.18.255.25516,382
77113.19.0.0/18113.19.0.1 to 113.19.63.254113.19.63.25516,382
78113.19.64.0/18113.19.64.1 to 113.19.127.254113.19.127.25516,382
79113.19.128.0/18113.19.128.1 to 113.19.191.254113.19.191.25516,382
80113.19.192.0/18113.19.192.1 to 113.19.255.254113.19.255.25516,382
81113.20.0.0/18113.20.0.1 to 113.20.63.254113.20.63.25516,382
82113.20.64.0/18113.20.64.1 to 113.20.127.254113.20.127.25516,382
83113.20.128.0/18113.20.128.1 to 113.20.191.254113.20.191.25516,382
84113.20.192.0/18113.20.192.1 to 113.20.255.254113.20.255.25516,382
85113.21.0.0/18113.21.0.1 to 113.21.63.254113.21.63.25516,382
86113.21.64.0/18113.21.64.1 to 113.21.127.254113.21.127.25516,382
87113.21.128.0/18113.21.128.1 to 113.21.191.254113.21.191.25516,382
88113.21.192.0/18113.21.192.1 to 113.21.255.254113.21.255.25516,382
89113.22.0.0/18113.22.0.1 to 113.22.63.254113.22.63.25516,382
90113.22.64.0/18113.22.64.1 to 113.22.127.254113.22.127.25516,382
91113.22.128.0/18113.22.128.1 to 113.22.191.254113.22.191.25516,382
92113.22.192.0/18113.22.192.1 to 113.22.255.254113.22.255.25516,382
93113.23.0.0/18113.23.0.1 to 113.23.63.254113.23.63.25516,382
94113.23.64.0/18113.23.64.1 to 113.23.127.254113.23.127.25516,382
95113.23.128.0/18113.23.128.1 to 113.23.191.254113.23.191.25516,382
96113.23.192.0/18113.23.192.1 to 113.23.255.254113.23.255.25516,382
97113.24.0.0/18113.24.0.1 to 113.24.63.254113.24.63.25516,382
98113.24.64.0/18113.24.64.1 to 113.24.127.254113.24.127.25516,382
99113.24.128.0/18113.24.128.1 to 113.24.191.254113.24.191.25516,382
100113.24.192.0/18113.24.192.1 to 113.24.255.254113.24.255.25516,382
101113.25.0.0/18113.25.0.1 to 113.25.63.254113.25.63.25516,382
102113.25.64.0/18113.25.64.1 to 113.25.127.254113.25.127.25516,382
103113.25.128.0/18113.25.128.1 to 113.25.191.254113.25.191.25516,382
104113.25.192.0/18113.25.192.1 to 113.25.255.254113.25.255.25516,382
105113.26.0.0/18113.26.0.1 to 113.26.63.254113.26.63.25516,382
106113.26.64.0/18113.26.64.1 to 113.26.127.254113.26.127.25516,382
107113.26.128.0/18113.26.128.1 to 113.26.191.254113.26.191.25516,382
108113.26.192.0/18113.26.192.1 to 113.26.255.254113.26.255.25516,382
109113.27.0.0/18113.27.0.1 to 113.27.63.254113.27.63.25516,382
110113.27.64.0/18113.27.64.1 to 113.27.127.254113.27.127.25516,382
111113.27.128.0/18113.27.128.1 to 113.27.191.254113.27.191.25516,382
112113.27.192.0/18113.27.192.1 to 113.27.255.254113.27.255.25516,382
113113.28.0.0/18113.28.0.1 to 113.28.63.254113.28.63.25516,382
114113.28.64.0/18113.28.64.1 to 113.28.127.254113.28.127.25516,382
115113.28.128.0/18113.28.128.1 to 113.28.191.254113.28.191.25516,382
116113.28.192.0/18113.28.192.1 to 113.28.255.254113.28.255.25516,382
117113.29.0.0/18113.29.0.1 to 113.29.63.254113.29.63.25516,382
118113.29.64.0/18113.29.64.1 to 113.29.127.254113.29.127.25516,382
119113.29.128.0/18113.29.128.1 to 113.29.191.254113.29.191.25516,382
120113.29.192.0/18113.29.192.1 to 113.29.255.254113.29.255.25516,382
121113.30.0.0/18113.30.0.1 to 113.30.63.254113.30.63.25516,382
122113.30.64.0/18113.30.64.1 to 113.30.127.254113.30.127.25516,382
123113.30.128.0/18113.30.128.1 to 113.30.191.254113.30.191.25516,382
124113.30.192.0/18113.30.192.1 to 113.30.255.254113.30.255.25516,382
125113.31.0.0/18113.31.0.1 to 113.31.63.254113.31.63.25516,382
126113.31.64.0/18113.31.64.1 to 113.31.127.254113.31.127.25516,382
127113.31.128.0/18113.31.128.1 to 113.31.191.254113.31.191.25516,382
128113.31.192.0/18113.31.192.1 to 113.31.255.254113.31.255.25516,382
129113.32.0.0/18113.32.0.1 to 113.32.63.254113.32.63.25516,382
130113.32.64.0/18113.32.64.1 to 113.32.127.254113.32.127.25516,382
131113.32.128.0/18113.32.128.1 to 113.32.191.254113.32.191.25516,382
132113.32.192.0/18113.32.192.1 to 113.32.255.254113.32.255.25516,382
133113.33.0.0/18113.33.0.1 to 113.33.63.254113.33.63.25516,382
134113.33.64.0/18113.33.64.1 to 113.33.127.254113.33.127.25516,382
135113.33.128.0/18113.33.128.1 to 113.33.191.254113.33.191.25516,382
136113.33.192.0/18113.33.192.1 to 113.33.255.254113.33.255.25516,382
137113.34.0.0/18113.34.0.1 to 113.34.63.254113.34.63.25516,382
138113.34.64.0/18113.34.64.1 to 113.34.127.254113.34.127.25516,382
139113.34.128.0/18113.34.128.1 to 113.34.191.254113.34.191.25516,382
140113.34.192.0/18113.34.192.1 to 113.34.255.254113.34.255.25516,382
141113.35.0.0/18113.35.0.1 to 113.35.63.254113.35.63.25516,382
142113.35.64.0/18113.35.64.1 to 113.35.127.254113.35.127.25516,382
143113.35.128.0/18113.35.128.1 to 113.35.191.254113.35.191.25516,382
144113.35.192.0/18113.35.192.1 to 113.35.255.254113.35.255.25516,382
145113.36.0.0/18113.36.0.1 to 113.36.63.254113.36.63.25516,382
146113.36.64.0/18113.36.64.1 to 113.36.127.254113.36.127.25516,382
147113.36.128.0/18113.36.128.1 to 113.36.191.254113.36.191.25516,382
148113.36.192.0/18113.36.192.1 to 113.36.255.254113.36.255.25516,382
149113.37.0.0/18113.37.0.1 to 113.37.63.254113.37.63.25516,382
150113.37.64.0/18113.37.64.1 to 113.37.127.254113.37.127.25516,382
151113.37.128.0/18113.37.128.1 to 113.37.191.254113.37.191.25516,382
152113.37.192.0/18113.37.192.1 to 113.37.255.254113.37.255.25516,382
153113.38.0.0/18113.38.0.1 to 113.38.63.254113.38.63.25516,382
154113.38.64.0/18113.38.64.1 to 113.38.127.254113.38.127.25516,382
155113.38.128.0/18113.38.128.1 to 113.38.191.254113.38.191.25516,382
156113.38.192.0/18113.38.192.1 to 113.38.255.254113.38.255.25516,382
157113.39.0.0/18113.39.0.1 to 113.39.63.254113.39.63.25516,382
158113.39.64.0/18113.39.64.1 to 113.39.127.254113.39.127.25516,382
159113.39.128.0/18113.39.128.1 to 113.39.191.254113.39.191.25516,382
160113.39.192.0/18113.39.192.1 to 113.39.255.254113.39.255.25516,382
161113.40.0.0/18113.40.0.1 to 113.40.63.254113.40.63.25516,382
162113.40.64.0/18113.40.64.1 to 113.40.127.254113.40.127.25516,382
163113.40.128.0/18113.40.128.1 to 113.40.191.254113.40.191.25516,382
164113.40.192.0/18113.40.192.1 to 113.40.255.254113.40.255.25516,382
165113.41.0.0/18113.41.0.1 to 113.41.63.254113.41.63.25516,382
166113.41.64.0/18113.41.64.1 to 113.41.127.254113.41.127.25516,382
167113.41.128.0/18113.41.128.1 to 113.41.191.254113.41.191.25516,382
168113.41.192.0/18113.41.192.1 to 113.41.255.254113.41.255.25516,382
169113.42.0.0/18113.42.0.1 to 113.42.63.254113.42.63.25516,382
170113.42.64.0/18113.42.64.1 to 113.42.127.254113.42.127.25516,382
171113.42.128.0/18113.42.128.1 to 113.42.191.254113.42.191.25516,382
172113.42.192.0/18113.42.192.1 to 113.42.255.254113.42.255.25516,382
173113.43.0.0/18113.43.0.1 to 113.43.63.254113.43.63.25516,382
174113.43.64.0/18113.43.64.1 to 113.43.127.254113.43.127.25516,382
175113.43.128.0/18113.43.128.1 to 113.43.191.254113.43.191.25516,382
176113.43.192.0/18113.43.192.1 to 113.43.255.254113.43.255.25516,382
177113.44.0.0/18113.44.0.1 to 113.44.63.254113.44.63.25516,382
178113.44.64.0/18113.44.64.1 to 113.44.127.254113.44.127.25516,382
179113.44.128.0/18113.44.128.1 to 113.44.191.254113.44.191.25516,382
180113.44.192.0/18113.44.192.1 to 113.44.255.254113.44.255.25516,382
181113.45.0.0/18113.45.0.1 to 113.45.63.254113.45.63.25516,382
182113.45.64.0/18113.45.64.1 to 113.45.127.254113.45.127.25516,382
183113.45.128.0/18113.45.128.1 to 113.45.191.254113.45.191.25516,382
184113.45.192.0/18113.45.192.1 to 113.45.255.254113.45.255.25516,382
185113.46.0.0/18113.46.0.1 to 113.46.63.254113.46.63.25516,382
186113.46.64.0/18113.46.64.1 to 113.46.127.254113.46.127.25516,382
187113.46.128.0/18113.46.128.1 to 113.46.191.254113.46.191.25516,382
188113.46.192.0/18113.46.192.1 to 113.46.255.254113.46.255.25516,382
189113.47.0.0/18113.47.0.1 to 113.47.63.254113.47.63.25516,382
190113.47.64.0/18113.47.64.1 to 113.47.127.254113.47.127.25516,382
191113.47.128.0/18113.47.128.1 to 113.47.191.254113.47.191.25516,382
192113.47.192.0/18113.47.192.1 to 113.47.255.254113.47.255.25516,382
193113.48.0.0/18113.48.0.1 to 113.48.63.254113.48.63.25516,382
194113.48.64.0/18113.48.64.1 to 113.48.127.254113.48.127.25516,382
195113.48.128.0/18113.48.128.1 to 113.48.191.254113.48.191.25516,382
196113.48.192.0/18113.48.192.1 to 113.48.255.254113.48.255.25516,382
197113.49.0.0/18113.49.0.1 to 113.49.63.254113.49.63.25516,382
198113.49.64.0/18113.49.64.1 to 113.49.127.254113.49.127.25516,382
199113.49.128.0/18113.49.128.1 to 113.49.191.254113.49.191.25516,382
200113.49.192.0/18113.49.192.1 to 113.49.255.254113.49.255.25516,382
201113.50.0.0/18113.50.0.1 to 113.50.63.254113.50.63.25516,382
202113.50.64.0/18113.50.64.1 to 113.50.127.254113.50.127.25516,382
203113.50.128.0/18113.50.128.1 to 113.50.191.254113.50.191.25516,382
204113.50.192.0/18113.50.192.1 to 113.50.255.254113.50.255.25516,382
205113.51.0.0/18113.51.0.1 to 113.51.63.254113.51.63.25516,382
206113.51.64.0/18113.51.64.1 to 113.51.127.254113.51.127.25516,382
207113.51.128.0/18113.51.128.1 to 113.51.191.254113.51.191.25516,382
208113.51.192.0/18113.51.192.1 to 113.51.255.254113.51.255.25516,382
209113.52.0.0/18113.52.0.1 to 113.52.63.254113.52.63.25516,382
210113.52.64.0/18113.52.64.1 to 113.52.127.254113.52.127.25516,382
211113.52.128.0/18113.52.128.1 to 113.52.191.254113.52.191.25516,382
212113.52.192.0/18113.52.192.1 to 113.52.255.254113.52.255.25516,382
213113.53.0.0/18113.53.0.1 to 113.53.63.254113.53.63.25516,382
214113.53.64.0/18113.53.64.1 to 113.53.127.254113.53.127.25516,382
215113.53.128.0/18113.53.128.1 to 113.53.191.254113.53.191.25516,382
216113.53.192.0/18113.53.192.1 to 113.53.255.254113.53.255.25516,382
217113.54.0.0/18113.54.0.1 to 113.54.63.254113.54.63.25516,382
218113.54.64.0/18113.54.64.1 to 113.54.127.254113.54.127.25516,382
219113.54.128.0/18113.54.128.1 to 113.54.191.254113.54.191.25516,382
220113.54.192.0/18113.54.192.1 to 113.54.255.254113.54.255.25516,382
221113.55.0.0/18113.55.0.1 to 113.55.63.254113.55.63.25516,382
222113.55.64.0/18113.55.64.1 to 113.55.127.254113.55.127.25516,382
223113.55.128.0/18113.55.128.1 to 113.55.191.254113.55.191.25516,382
224113.55.192.0/18113.55.192.1 to 113.55.255.254113.55.255.25516,382
225113.56.0.0/18113.56.0.1 to 113.56.63.254113.56.63.25516,382
226113.56.64.0/18113.56.64.1 to 113.56.127.254113.56.127.25516,382
227113.56.128.0/18113.56.128.1 to 113.56.191.254113.56.191.25516,382
228113.56.192.0/18113.56.192.1 to 113.56.255.254113.56.255.25516,382
229113.57.0.0/18113.57.0.1 to 113.57.63.254113.57.63.25516,382
230113.57.64.0/18113.57.64.1 to 113.57.127.254113.57.127.25516,382
231113.57.128.0/18113.57.128.1 to 113.57.191.254113.57.191.25516,382
232113.57.192.0/18113.57.192.1 to 113.57.255.254113.57.255.25516,382
233113.58.0.0/18113.58.0.1 to 113.58.63.254113.58.63.25516,382
234113.58.64.0/18113.58.64.1 to 113.58.127.254113.58.127.25516,382
235113.58.128.0/18113.58.128.1 to 113.58.191.254113.58.191.25516,382
236113.58.192.0/18113.58.192.1 to 113.58.255.254113.58.255.25516,382
237113.59.0.0/18113.59.0.1 to 113.59.63.254113.59.63.25516,382
238113.59.64.0/18113.59.64.1 to 113.59.127.254113.59.127.25516,382
239113.59.128.0/18113.59.128.1 to 113.59.191.254113.59.191.25516,382
240113.59.192.0/18113.59.192.1 to 113.59.255.254113.59.255.25516,382
241113.60.0.0/18113.60.0.1 to 113.60.63.254113.60.63.25516,382
242113.60.64.0/18113.60.64.1 to 113.60.127.254113.60.127.25516,382
243113.60.128.0/18113.60.128.1 to 113.60.191.254113.60.191.25516,382
244113.60.192.0/18113.60.192.1 to 113.60.255.254113.60.255.25516,382
245113.61.0.0/18113.61.0.1 to 113.61.63.254113.61.63.25516,382
246113.61.64.0/18113.61.64.1 to 113.61.127.254113.61.127.25516,382
247113.61.128.0/18113.61.128.1 to 113.61.191.254113.61.191.25516,382
248113.61.192.0/18113.61.192.1 to 113.61.255.254113.61.255.25516,382
249113.62.0.0/18113.62.0.1 to 113.62.63.254113.62.63.25516,382
250113.62.64.0/18113.62.64.1 to 113.62.127.254113.62.127.25516,382
251113.62.128.0/18113.62.128.1 to 113.62.191.254113.62.191.25516,382
252113.62.192.0/18113.62.192.1 to 113.62.255.254113.62.255.25516,382
253113.63.0.0/18113.63.0.1 to 113.63.63.254113.63.63.25516,382
254113.63.64.0/18113.63.64.1 to 113.63.127.254113.63.127.25516,382
255113.63.128.0/18113.63.128.1 to 113.63.191.254113.63.191.25516,382
256113.63.192.0/18113.63.192.1 to 113.63.255.254113.63.255.25516,382

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.